The invention relates to a sealed connector in accordance with the preamble of claim 1 and a method of sealing a connector in accordance with the preamble of claim 13.
Control elements of the hydraulics, for example valves, can be actuated electromagnetically. For this purpose the valve includes an encapsulated solenoid having a coil via the current feed of which an armature is moved that entrains a valve piston. In this way a position of the valve piston can be precisely adjusted. For the current supply of the coil a connector penetrating the casing which is preferably made of plastic material and is injection-molded to the casing is provided at the casing of the solenoid. Current paths or pins of the connector connectable to a power source pass through a connector bottom of the connector from an outside toward an inside of the casing where they are connected to the coil.
It is known to pot the connector bottom of the connector with a dielectric sealing compound so as to seal the passage of the current paths against penetrating moisture. To this end, usually plastic materials, epoxy resin or silicone rubber is utilized.
The document DE 1 148 613 dating from 1963 recommends as a sealing compound for the connector a silicone to be potted which is intended to adhere to the contacted materials. Alternatively, tacky petroleum compounds or rubber or epoxy compounds are suggested.
It is a drawback of the suggested solutions that the substances suggested as sealing compound are not specified. It is a drawback of the suggested epoxy compounds that especially in the case of load due to temperature variations they are subjected to shrinking which may result in a detachment and thus in leakage at a boundary layer between the pin and the sealing compound.
The document DE 44 10 455 C1 dating from 1995 takes up the recommendation of using an adherent silicone and mentions the use of a two-component UV-hardening silicone. However, the document advises against this concept, as in the case of mechanical load of the silicone, especially in the case of movement of the contact pins, the adhesiveness of the silicone gets lost. Instead a solution is suggested in which the tightness is obtained by a specific geometric design of the pins and a shrinking of the plastic material surrounding the pins during cooling of the plastic material in the manufacturing process.
It is a drawback of the solution without any sealing compound that the plastic material surrounding the pins is subjected to shrinking during its lifetime. Furthermore, the plastic material is only little elastic so that with this solution, too, leakage of the passage can occur in the case of recurring mechanical loads or in the case of load due to temperature variations.
Compared to this, the object underlying the invention is to provide a connector having improved tightness against penetrating moisture.
This object is achieved by a sealed connector comprising the features of claim 1 as well as by a method of sealing a connector comprising the features of claim 13.